Midtown Manhattan’s “Plaza District” is the area around the Plaza Hotel (at Central Park South/59th Street and Fifth Avenue). Wikipedia defines the Plaza District as “between 42nd Street and 59th Street, from Third Avenue to Seventh Avenue.” The New York (NY) Times article “Renewals Active in Plaza District,” on May 23, 1937, described “the Plaza district centering in Fifth and Madison Avenues, between Fiftieth, and Sixty-second Street.” The New York (NY) Times article “The Plaza District: Catering to Midtown Office Needs” by Alan S. Oser, on November 2, 1986, cited the real estate firm of Cushman & Wakefield on a “Plaza District” from 47th to 65st Street and from Seventh Avenue to the East River. The Plaza District—like the Plaza Hotel—is very expensive and is sought after for executive offices.
   
“Plaza District” was cited and explained—perhaps for the first time—in the New York (NY) Times, “Vacancy Surveys for Manhattan: Borough Is Divided Into Seven Districts by Building Managers,” on March 10, 1929:
 
“The ‘Plaza’ district, of which Lawrence B. Cummins, vice president of Douglas & Co., is vice chairman, embraces the area between the north side of Fiftieth Street and the south side of Sixty-second Street and from the west side of Second Avenue to midway between Sixth and Seventh Avenues.”
   
   
Wikipedia: Midtown Manhattan
Midtown Manhattan, or simply Midtown, is a geographic area of Manhattan, New York City. It is home to some of the city’s most iconic buildings, including the Empire State Building, the Chrysler Building, and the United Nations Headquarters. It contains world-famous commercial zones such as Rockefeller Center, Broadway, and Times Square.
 
Geographically, Midtown is commonly defined as the area south of 59th Street, east of the Hudson River, west of the East River, and though its southern border is less clear, most consider it to be somewhere between 14th Street and 30th Street. Overall, Manhattan can be divided into three geographic regions: “Uptown”, Midtown, and “Downtown”.
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Different definitions of Midtown Manhattan
The border of Midtown Manhattan is nebulous and further confused by the fact that the term “Midtown Manhattan” can be used to refer either to a district or a group of neighborhoods and districts in Manhattan. The area between 14th and 86th streets includes roughly the center of Manhattan; however, the term Midtown Manhattan can also apply to the area between 31st street and 59th Streets, although there are still office buildings south of 31st street, many of them, such as the MetLife Tower, quite early relative to those in Midtown proper (commonly referred to simply as “Midtown”). The “Plaza District”, a term used by Manhattan real estate professionals to denote the most expensive area of midtown from a commercial real estate perspective, lies between 42nd Street and 59th Street, from Third Avenue to Seventh Avenue, about a square kilometer or half a square mile.
 
Wikipedia: Plaza Hotel
The Plaza Hotel, located in the borough of Manhattan, New York City, is a landmark 20-story luxury hotel with a height of 250 ft (76 m) and length of 400 ft (120 m) that occupies the west side of Grand Army Plaza, from which it derives its name, and extends along Central Park South in Manhattan. Fifth Avenue extends along the east side of Grand Army Plaza. The Plaza Hotel is recognized as a Historic Hotel of America by the National Trust for Historic Preservation.
 
10 March 1929, New York (NY) Times:
VACANCY SURVEYS FOR MANHATTAN;
Borough Is Divided Into Seven Districts by Building Managers.
Manhattan Borough has been divided into seven districts by the Building Managers and Owners’ Association of New York to facilitate the compilation of its vacancy surveys of office, loft and apartment house buildings.
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The “Plaza” district, of which Lawrence B. Cummins, vice president of Douglas & Co., is vice chairman, embraces the area between the north side of Fiftieth Street and the south side of Sixty-second Street and from the west side of Second Avenue to midway between Sixth and Seventh Avenues.
 
23 May 1937, New York (NY) Times:
RENEWALS ACTIVE IN PLAZA DISTRICT;
Tenants Keeping Old Space in Fifth and Madison Avenue Section
Brisk renewals of commercial leases are providing the feature of the Spring-renting season in the Plaza district centering in Fifth and Madison Avenues, between Fiftieth, and Sixty-second Street, according to members of the office-building group of the Plaza district rentals conditions committee of the Real Estate Board of New York.
 
9 January 1966, New York (NY) Times:
PLAZA AREA BUSY IN POSTWAR BOOM; 35 Structures Erected in Midtown District Since ‘47
Manhattan’s midtown Plaza district has received a generous share of the many new structures provided by the postwar building boom 35 since 1947.
 
1 January 1967, New York (NY) Times, Real Estate section, pg. 162:
SPACE IS SCARCE IN PLAZA DISTRICT;
Office Leasing In East Side Area Below 60th Street Is a Landlord’s Market
VACANT QUARTERS RARE
Demand Exceeds the Supply Despite the Addition of 38 Buildings in Decade
By FRANKLIN WHITEHOUSE
The search for office space in Manhattan’s gleaming Plaza district, as intense as that for secretaries with English accents, has resulted in the tightest leasing market in town.
 
New York (NY) Times
PERSPECTIVES: THE PLAZA DISTRICT; Catering to Midtown Office Needs
By ALAN S. OSER
Published: November 2, 1986
STUDENTS of the city’s office market have rarely been content to divide Manhattan merely into the two commercial districts of midtown and downtown. They see submarkets within each, especially in the midtown area.
 
Thus midtown becomes, for one brokerage firm, Midtown North and Midtown South. Others speak of Midtown South, the Grand Central District, the West Side and the Plaza District. For still others, submarkets follow the avenues -Fifth and Madison Avenues are one grouping and Second, Third and Lexington Avenues are analyzed separately.
 
As it happens, there is a modest burst of construction in progress in a subsection of a subsection - the East 60’s near Madison Avenue, which some consider part of the Plaza District, so named because it includes the Plaza Hotel, at Fifth Avenue and 59th Street. Boundary definitions differ, but according to an inclusive one by Cushman & Wakefield, the brokerage firm, it runs from 47th to 65st Street, from Seventh Avenue to the East River, and contains 82.8 million of midtown’s 215 million square feet of office space.
 
OCLC WorldCat record
Plaza district, Midtown & the Upper East Side, New York City : the essential guide to shopping, art galleries, restaurants, museums and more for the urban traveler : the companion guide to Red Maps’ NYC and SoHo maps : the red map.
Author: West 16th Street Map Company.
Publisher: [New York : West 16th Street Map Co.], ©1998.
Edition/Format: Map : English
   
New York (NY) Times
Not Exactly Cheap Chic, but Closer
By J. ALEX TARQUINIO
Published: July 7, 2009
Back when financial markets were still bubbling, hedge fund managers and private equity gurus flocked to the Plaza District, pushing up rents and crowding out some of the neighborhood’s traditional tenants, like apparel designers and art dealers. Eventually, one of Manhattan’s most fashionable office markets — which is centered in the East 50s and takes its name from the Plaza Hotel — became unattainable to all but the lords of high finance.
   
Google Books
The Great Hangover:
21 Tales of the New Recession from the Pages of Vanity Fair
Edited by Graydon Carter
New York, NY: HarperCollins Publishers
2010
Pg. 82:
In New York, the place to be was “the Plaza District”—the area stretching from Park Avenue to Sixth Avenue, just south of Central Park.
   
The Street
SL Green Realty Corp. Announces Agreement To Acquire 10 East 53rd Street
BY Business Wire |  01/10/12 - 08:00 AM EST
SL Green Realty Corp. (NYSE: SLG), New York City’s largest commercial office landlord, today announced it has entered into an agreement to acquire 10 East 53rd St., a 37-story, 390,000-square-foot Midtown Manhattan office building. The purchase price is $252.5 million, or approximately $647 per square foot.
 
The Class A building was constructed in 1972 and is located in New York’s Plaza District between 5th and Madison Avenues, and is currently the headquarters of Harper Collins.
 
Bloomberg.com
New York Plaza District Offices Empty as Banks Cut Space
By David M. Levitt - Sep 28, 2012 1:07 PM ET
Manhattan’s Plaza district, the area near Central Park that commands the nation’s highest office rents, has a glut of space as financial firms cut back and tenants seek trendier neighborhoods south of Midtown.
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The Plaza district—the area between Sixth Avenue and the East River from 47th to 65th streets, anchored by the landmark Plaza Hotel at Fifth Avenue and Central Park South—is home to some of the nation’s most expensive and prestigious office towers, including the General Motors Building and 9 W. 57th St. About 30 percent of the market is financial-service firms, which have announced about 60,000 job cuts worldwide this year, according to data compiled by Bloomberg.